Depends on the person you get handling your case. I didn't have a letter really, just randomly walked into a branch and asked to reopen a CIMB account again since all of mine went dormant. Only had the MCO letter with me that time since I did it out of the blue which was enough "evidence" for her that I was employed. The more idiotic the person handling the case is, the less likely it is that they'll let you open an account. Just find another person and should be able to settle easily.